Although it has been observed that patients describe marked symptomatic benefit and improved exercise capacity 2-4 years after the performance of percutaneous transluminal coronary angioplasty (PTCA), little data is available documenting anatomic and functional results during long-term follow-up. Thus, 28 of the first 30 patients who had a successful procedure, and had not had clinical or anatomical evidence of restenosis in the first 9 months after the procedure, were reevaluated at an average of 37 months after their last successful procedure. At follow-up patients underwent cardiac catheterization, treadmill exercise testing and radionuclide angiography at rest and with exercise. The percent diameter narrowings pre-PTCA was 67+14% and improved to 31%+14% immediately after the procedure. It was 28+14% six months later and 20+14% at late follow-up. The last measurement is statistically significantly less than the narrowing found at the 6 month study. Treadmill exercise time was 7.5+7 minutes pre-PTCA and improved to 17.2+7, 19.8+7, and 17.5+7 minutes at the three respective post-PTCA studies. No change occurred in rest LV ejection fraction (EF) after PTCA, but exercise LVEF, which had fallen by 4.3+7.5% pre-PTCA (compared to rest), rose after PTCA by 8.2+7.5, 4.7+7.5% and 4.6+17.5% respectively. Fifteen patients showed a greater than 10% decrease in the amount of narrowing at the angioplasty site between the six month and three year studies. Two patients developed new significant stenoses at nondilated sites during follow-up. These results indicate that the short-term anatomic and functional success after PTCA is maintained for at least three years, even though disease occasionally progresses at other sites.